Need help with budget build

Hey guys, I'm trying to build an eBike because I need some transportation to finish school and apply for more jobs. I was trying for under $500, but it doesn't look like that's very viable, so I'm looking for the best value for as cheap as possible.

I'm not looking for anything spectacular.

• 
  With moderate pedaling:
• 15-20 mph
• 10-20 miles range
• mostly level terrain
• I weigh under 200lbs
• 26" wheels, steel frame, 7 speed - (This bike)
• Location: Sacramento, CA

I love learning new things and building and fixing things, so anything that can be done DIY for cheaper I want to do, except build a battery because I don't have a spot welder.
I have a battery charger for RC trucks, can this be used to charge a bike battery? http://hitecrcd.com/products/chargers/acdc-chargers/x1-ac-plus-battery-charger/product

Here's what I think I want so far:

• 36v (edit: cost doesn't seem much different for 48v, so might as well)
• 10Ah+
• 350w+
• brushless
• geared or DD both seem fine for me. Geared has a slight edge in-case battery dies?
• back wheel hub

Should I be looking for a kit or for each component separately? What else do I need to know?

I keep reading these threads where folks come in and ask for a really low budget build and thread goes on to discuss regenerative braking, cycle analyst etc. I'm also a newb and a bit of a minimalist so here's a different perspective. Remember I'm not an expert just sharing a slightly educated opinion from another newb.

* Keep it simple with electronics. Low voltage cut-off in the controller is all you need. It's not like you don't know approximately how many miles have you traveled and when the battery is going to run out -- after a few rides you'll know pretty well. Simple $10 voltmeter would work for a fuel gauge too.


* Don't go anywhere near RC LiPos. They're the wrong kind of a battery for your application. You don't need high current, you need safe, reliable, and good energy density.


* http://lunacycle.com/48v-samsung-18650-battery-pack-10ah/

This IMHO is a killer deal on a well constructed pack with BMS and brand name cells. Not exactly the cutting edge anymore but solid and a great value. Grab a 3A charger while at it too, your RC charger is going to be a PITA to deal with and with the pack above you won't have to ever worry about balancing so just get the $35 charger and be done with it. 500Wh is plenty of juice. Sacto is just about flat so it'll likely do 20 miles no problem. Hills is what kills range, and speeds over 20mph come close second.


* Rear wheel is a lot more of a potential PITA to get everything to match up. If you want a budget build grab a front hub. No hassle with figuring out what freewheel you need, chainline stays as is, etc.


* If you can help it throw that walmart special bike into the trash and get some quality used road bike off Craigslist. If you're fit you don't need suspension or any of this other crap. If you're fit you don't need gears either, electric motor will pull you up to cruising speeds just fine so get a single gear for top speed and you'll be fine. Tires on that bike will sap range pretty good too, road tires would be much better.

* Get geared front mini hub that will do 20mph in whatever wheel size you end up with, 15A controller ($15), and go ride!

Read this and fill in the gaps. I've got over 10K miles on my Ledge 2.1.
http://endless-sphere.com/forums/viewtopic.php?f=3&t=70169
$500 will be more than enough if you know what to buy.

Yeah after reading around, I don't think I want to use RC Lipo. And I need to tell my dad to be more careful with his RC truck batteries. I think we're lucky to not have a fire yet

What do you guys think about these:

http://www.leafbike.com/products/diy-bike-conversion-kit/26-inch-electric-hub-motor-kit/26-inch-36v-750w-rear-hub-motor-bike-conversion-kit-622.html + http://lunacycle.com/36v-18650-20ah-ebike-battery-pack/
or
http://www.leafbike.com/products/diy-bike-conversion-kit/26-inch-electric-hub-motor-kit/26-inch-48v-1000w-rear-hub-motor-bike-conversion-kit-620.html + http://lunacycle.com/48v-samsung-18650-battery-pack-10ah/

YonderGod said:

Yeah after reading around, I don't think I want to use RC Lipo. And I need to tell my dad to be more careful with his RC truck batteries.

Click to expand...

Learning that by your 2nd day on ES is a great accomplishment.

Used stuff is the route to making your money go further, and batteries salvaged from electric cars are often the best value. One example is the cells or packs that Okashira was selling that they made from a like new Tesla ModelS pack.http://endless-sphere.com/forums/viewtopic.php?f=9&t=67661 They sold out, but from today's post it looks like they may get another Tesla pack soon. If prices are the same you'd be looking at about $250 for a 36V15.5ah pack including pack assembly and shipping. I always suggest going with more battery than originally planned to keep DODs (Depth Of Discharge) discharge rates more conservative for better battery life and longer range.

An added benefit with used batteries is that if they're still in balance, then the cells are already proven to be free of defects. As an example I've got packs I made from used toolpack cells back in 2008 that are still going strong, though capacity is somewhat diminished. Back then they were the only "safe" cells capable of ebike power, and were rated for only a 500 cycle life. I've gotten several times greater than that.

Used motors is a great way to go too. Unless you can find something locally that you can easily test, then stick with ES members and be sure to verify that the motor is in good working order. I just saw that Neptronix is interested in selling his Leaf motor, and it's not even in the for sale section yet.

BTW, the link for your bike said it is an aluminum frame. If you don't already have it, then buying something used locally is the way to go. Bring a magnet with you to verify steel or aluminum.

In the meantime buy yourself an ebike tester, and if you don't already have a digital multimeter, get one of those too.

Get your father on board with the plan to expand your budget. Let him know that geezers probably older than he are having much more fun with ebikes. It's like having an RC that's big enough to ride.

John

Have you checked Craigslit, it's surprising what e-bike stuff you can find there for a budget minded person. (I got my bike there, dumped the SLAs and went my RC lithiums, all for much cheaper than i could do a ebay-hub kit.) Even adding my repairs (2 tires, 4 tubes, some gears, a CellLog8 and now a SignalAB BMS), I'll still under $400 all in.


E.g. in your area is someone selling Lifepo4 batteries (not great but viable entry level VPower brand)
http://sacramento.craigslist.org/bop/5110195925.html

And if you have a friend that can give you a ride to pick up there are even some complete bikes
http://sfbay.craigslist.org/scz/bik/5129408009.html
http://sfbay.craigslist.org/sfc/bik/5129535667.html

and a kit.. a bit farther away
http://sfbay.craigslist.org/eby/bik/5123643202.html


I see you've decided no to do lipo. If you flip-flop again, either look at a BMS to go with them or at least get at CellLog8 or something else to make it easy to check the voltages every day. You would likely quickly tire of charging with the

I was looking at some used stuff, specifically that battery on craigslist, but I don't like buying used things that I can't test before I buy and don't know a lot about. I'll keep an eye on the forums though.

Regarding my bike, the center part is aluminum, but the rear and front are steel, I checked with a magnet.

Note that one of the motors that you listed is "V" brake only while one accommodates disc too.
Look at ebay for a well respected YESCOM 48V, 1000w kit for $250 or so delivered (company is acceries or similar)..

Fill in your location in your profile and then people can make recommendations.
http://endless-sphere.com/forums/viewtopic.php?f=3&t=66302

2old said:

Note that one of the motors that you listed is "V" brake only while one accommodates disc too.
Look at ebay for a well respected YESCOM 48V, 1000w kit for $250 or so delivered (company is acceries or similar)..

Click to expand...

http://www.ebay.com/itm/36V800W-26-Rear-Wheel-Electric-Bicycle-Motor-Kit-PAS-Cycling-Hub-Conversion-Kit-/371297071158?pt=LH_DefaultDomain_0&hash=item567307b036
http://www.ebay.com/itm/48V1000W-26-Rear-Wheel-Electric-Bicycle-Motor-Kit-E-Bike-Cycling-Hub-Conversion-/231520160623?pt=LH_DefaultDomain_0&hash=item35e7ad4b6f

$206 shipped, I like.

I don't really need the 48v, but if it's the same price, why not?
Only thing is my bike is 7 speed, and the 48v has a 6 speed freewheel, will this be a problem?

wesnewell said:

Fill in your location in your profile and then people can make recommendations.
http://endless-sphere.com/forums/viewtopic.php?f=3&t=66302

Click to expand...

I put my location in my post, but okay, Ill do that too

The Leafbike site you saw includes an LCD screen that will give you some needed info about your speed and battery. The cheaper ebay kit does not. But then again, there is always something a little better for a little more money. That makes keeping in budget tricky.

The 36 volt kits meet your needs. However, it may not be what you ultimately want.
If you are the kind of person who likes to watch golf, Is passionate about traditional needlepoint, and enjoys spending their Friday night at the library cataloging their stamp collection, then 36 volts will be a good match for you.
If you are the kind of person who would only watch golf if it was played with live hand grenades, Is passionate about Tattoo needle work, and enjoys spending their Friday night [ CENSURED AND REDACTED ] behind the library with a girl who's name you learned only after seeing her Tramp Stamp, then 48 volts is a better match for you.

Drunkskunk said:

The Leafbike site you saw includes an LCD screen that will give you some needed info about your speed and battery. The cheaper ebay kit does not. But then again, there is always something a little better for a little more money. That makes keeping in budget tricky.

The 36 volt kits meet your needs. However, it may not be what you ultimately want.
If you are the kind of person who likes to watch golf, Is passionate about traditional needlepoint, and enjoys spending their Friday night at the library cataloging their stamp collection, then 36 volts will be a good match for you.
If you are the kind of person who would only watch golf if it was played with live hand grenades, Is passionate about Tattoo needle work, and enjoys spending their Friday night [ CENSURED AND REDACTED ] behind the library with a girl who's name you learned only after seeing her Tramp Stamp, then 48 volts is a better match for you.

Click to expand...

There is a simple battery level indicator on the throttle on the ebay kit, is that good enough? If not, what would I need to buy with it? I have a phone app to tell my speed.
Oh also, the leafbike kit doesn't come with a freewheel, so that's an extra $25, and the ebay kit comes with a tire, I'm sure it's not a great quality tire, but it's probably better than the one I have.

I'll get the 48v then

About the only thing i wouldn't buy personally is a used battery, unless I absolutely trusted the person who is selling it. The best to spend money is on a good battery imho.

It seems to me, that if you are comitted to that Mongoose model, the first question should be; "Where to mount the battery?"
The review states that there are no water bottle bracket mounting bosses and even if you were to install some, the space looks tight both above and below the down tube.
That would dictate a rear rack mounted battery.
In the interest of some overall bike balance, it seems to me a frt. mounted motor would be the logical way to proceed.
But, those forks do not look to be overly strong, so, I would limit it to a low-powered geared mini-motor.
So general configuration would be, a low powered()ess than 800 Watts)frt. geared mini(like the "Cute" Q100) and a rear rack Li-Ion rack battery.

I don't see any big reasons to buy a new bike right now. Ill probably get one later, but for now I need to save as much money as possible.
I'm sure I can figure something out for the battery mount. I was thinking about even just putting it in a backpack with a cable sticking out, I don't want to leave it on my bike when I'm not on it anyways.

You will rethink that "battery in the back pack "solution after about two miles on a warm day.

That lunacycle battery is only 250 x 90 x 80 mm, it can probably even fit into one of the bigger handlebar bags although that'd be goofy as all get out. The $20 triangle bag from Amazon that I used to carry two HK lipo's in is about 26cm on the long end so maybe a couple cm too short and a couple too skinny for that battery. Maybe there's a slightly bigger triangle bag out there that'll still work.

Nah forget triangle bag, the thing not only has a very long rocker link but a super long chainstay too, no room in the triangle.

While I decided to rebuild my battery, I was just recently looking at lots of batteries. Given you want new battery and while am limited to 24v/ 29.4v pack, I looked at lots. While the 48v luna suggested by dakh is nice you might want to consider
http://lunacycle.com/36v-18650-20ah-ebike-battery-pack/

For $10 less, It will give you more range than the 48v 10ah pack, as it has nearly double the number of 18650 cells) tough at 36v you won't be going as fast, with more Ah, the battery will last a lot more cycles as you won't be drawing as much current from a cell. The 48v10ah would probably get you 20 miles if you take it reasonable speeds, but you'd be stressing the batteries more.


I tried a backpack when I was experiment with my first Lipo setup, it means a much longer cable and the batteries bounce around a lot more. Since I am (and you seem to be about to be) commuting on bike, I recommend a rear bike rack I got my for <$20 on ebay. I keep extra bungee cords on so i can also use it for books/lunch or other items get bigger/heaverier than one backpack full. I now have the battery frame mounted which I like much better -- I've not had problem with anyone messing with it with school over the past year.

Most people soon tire of 20mph top speed and wish they had gone with something a little faster. My initial purchase was a 48V 500W DD kit. It worked great but only had a top speed around 25 mph on 14s lipo. I'm an old fart close to 70, and I watch golf because I loved playing when I could, but I never liked playing behind slow people. I bought a 48V 1000W kit 2 weeks after the the 500W kit and that what I still ride today some 4+ years later. It topped out over 30 mph on 14s lipo and I was happy with that for a while. About a year later I wanted more. Today I run the same motor with another controller on 24s lipo on the ledge 2.1 I bought almost 3 years ago. There's no problem using a 7sp freewheel with it. The swing arm is steel and easily spread to work with it. I would never use a front motor on any bike other than a delta trike. Just too dangerous imo, and I've done 61+ mph on my bike going DH. Take your pick of these kits.
http://www.ebay.com/sch/i.html?_from=R40&_sacat=0&_nkw=48v1000w%20rear&LH_PrefLoc=1
As for the Battery pack, I use nothing but RC lipo and have never had a problem with it in over 4 years of use. Got about 13K miles on my current 3+ year 24s pack. A 10ah 12s pack will get you 28mph top speed and about a 20 mile range at 20mph for ~$160. Add a 12s bms and charger for another $50 or so and you will be well within your $500 budget and get years of use from your system. If you don't want to use rc lipo, then expect to pay a lot more for a battery pack capable of handling the current draw of the controller.
I also highly recommend one of these connected to the controller side of the battery connection for a fuel gauge for lipo.
http://www.ebay.com/itm/DC-15-to-120V-Waterproof-Red-LED-Panel-Meter-DC-Digital-Voltmeter-Two-wire-NIGH/141365876290

What do you guys think of these from BMS Battery?

https://bmsbattery.com/ebike-kit/529-q11-48v1kw-rear-driving-e-bike-conversion-kit-ebike-kit.html OR https://bmsbattery.com/ebike-kit/348-bafang-bpm2-48v500w-rear-driving-bike-conversion-kit-ebike-kit.html
https://bmsbattery.com/ebike-battery/166-48v10ah-li-ion-shrink-tube-ebike-battery-pack-ecitypower-battery.html


The total comes out to $518, which is about $100 cheaper than the ebay kit + luna cycle battery.
http://www.ebay.com/itm/48V1000W-26-Rear-Wheel-Electric-Bicycle-Motor-Kit-E-Bike-Cycling-Hub-Conversion-/231520160623?pt=LH_DefaultDomain_0&hash=item35e7ad4b6f
http://lunacycle.com/48v-samsung-18650-battery-pack-10ah/

What BMSbattery sells is often good. And people usually get what they order. What I think of BMSbattery isn't printable. Sadly someone at BMSbattery mistranslated "Customer service" as "servicing customers".

The first motor you linked from them isn't suitable with their battery. The battery has too low of an amperage output to safely handle a large motor. Only 15 amps. The second motor and battery combo from them would be good. This combo would be vastly less powerful than the Ebay kit. You also need to figure shipping from China would run $100-200 on top of their price.

Ah I knew I was forgetting something.

I need 1000w / 48v = 20.8 amps?
And is that continuous or peak amps?

Would this one be okay? https://bmsbattery.com/ebike-battery/685-48v10ah-bottle-09-e-bike-battery-charger-battery.html


I am including tax and shipping costs.

Yep, buy all that stuff from BMSbattery and then come back in a couple of months and let us know how that works out for you and what the total cost with shipping was. That is if you have it all within 2 months. I'm done. Good luck.

YonderGod said:

What do you guys think of these from BMS Battery?

https://bmsbattery.com/ebike-kit/529-q11-48v1kw-rear-driving-e-bike-conversion-kit-ebike-kit.html OR https://bmsbattery.com/ebike-kit/348-bafang-bpm2-48v500w-rear-driving-bike-conversion-kit-ebike-kit.html
https://bmsbattery.com/ebike-battery/166-48v10ah-li-ion-shrink-tube-ebike-battery-pack-ecitypower-battery.html


The total comes out to $518, which is about $100 cheaper than the ebay kit + luna cycle battery.
http://www.ebay.com/itm/48V1000W-26-Rear-Wheel-Electric-Bicycle-Motor-Kit-E-Bike-Cycling-Hub-Conversion-/231520160623?pt=LH_DefaultDomain_0&hash=item35e7ad4b6f
http://lunacycle.com/48v-samsung-18650-battery-pack-10ah/

Click to expand...

IMHO... You don't have the budget to take risks. All this shipped from China stuff can work, but you can also get screwed. What are the cells in those packs? We don't know, likely either rejects from a big brand or no name iffy stuff. If you get a bad cell or two in that pack after a few months, what are you gonna do? If you get a battery from LunaCycle with Samsung cells, you are very unlikely to run into trouble and if you do you get support from an almost-local-to-you vendor. If this shipped from China battery fails, even if they will be willing to do something about that (not likely), shipping stuff back and forth makes it both cost prohibitive and also will take a very long time.

For motor and controller I personally also would want something that is a widely used model and cheap, so that if something goes bust I can just order a replacement. Say these Cute Q100 motors, even if you burn one out you could just take the guts out and replace them with guts from a new motor, no need to re-lace the whole wheel. Controllers are $15. If you can build your own wheel you can be rolling for similar money but now you've got a system that you can service yourself and get cheap replacement parts if shit fails.

If you can wait a bit I'll likely have a couple of those motors for sale, they shipped wrong ones to me and those are actually the ones you'd want.